Abstract:
The maternal immunoglobulins acquired through the colostrum play a significant role in the defense mechanism of lamb against neonatal diseases until its own immune system is primed and produces significant amount of antibodies. The absorption of these immunoglobulins from the intestine is maximum during first six hours of life and no absorption occurs 24-36 hours postpartum. Neonatal lambs with failure or partial failure of passive transfer of immunoglobulins have higher rate of morbidity and mortality. Litter size and birth weight has significant effect on the absorption of immunoglobulins and mortality rate. The concentration of these maternal immunoglobulins in circulation at 24 hours after birth can be used as an indication of immunity or susceptibility of lambs to neonatal diseases. Several tests like zinc sulphate turbidity test, sodium suplhate turbidity test, refractometery, glutaraldehyde coagulation test, latex agglutination test, radioimmuno diffusion, radioimmunoassay, electrophoresis and ELISA have been developed for determination of immunoglobulin status. Among these, zinc sulphate turbidity test is simple to perform in laboratory and refractometery under field conditions.
